射影變換 的英文怎麼說
中文拼音 [shèyǐngbiànhuàn]
射影變換
英文
projective change-
Based on projective geometry, the research works about 3d invariance ' s extraction and application have been done in this thesis as following : ( 1 ) the basic theories and concepts in projective geometry are systematically summarized. it includes : the camera models of perspective imaging, projective collineation, cross ratio, a simple compare about invariance ( invariant ) among some geometry transformations, fundamental matrix, epipolar and epipolar line in epipolar geometry, and so on. ( 2 ) the calculation methods for 2d projective transformation are extended from points to multi - element, which includes points, lines, points lines and so on, to get the relationship between two projective planes
基於射影幾何理論,論文圍繞3d不變特徵的提取和應用進行了如下的研究工作: ( 1 )系統總結了射影幾何中的若干基礎概念,包括:透視成像的相機模型、射影對應、交比不變量、基於不同幾何變換下的不變量的簡單對比、對極幾何中的基礎矩陣、對極點、對極線等。Necessary and sufficient condition of 2 - dimension projective transformation being involution
二維射影變換是對合的充要條件Projective transformation of rational quadratic bzier curves
曲線的射影變換In the paper, we describe the whole configuration of the joint transform correlator ; introduce the correlative theories of joint fourier transform in detail ; in order to achieve better correlation result, the nonlinear processing of joint transform power spectrum ( jtps ) is put forward, the effect of jtps laplace sharpening and binary processing to the correlation image is given ; the method of the best binary threshold is determined ; we analyse the correlation image, present the way that removes liquid crystal diffraction spot, direct current spot and image noise, and binarize the correlation image finally
本論文主要對提出的聯合變換相關的整體結構進行了描述;詳細介紹了聯合傅里葉變換的相關理論;為了得到更好的相關結果,本文提出對聯合功率譜進行非線性處理的方法,給出了聯合變換功率譜的拉普拉斯銳化和譜的二值化處理對相關峰圖像的影響及二值化最佳閾值的確定方法;對相關峰圖像信息進行了分析;提出了消除液晶衍射光斑、直流光斑和圖像噪聲的方法;最後對相關峰圖像進行了二值化處理。By taking advantages of epipolar line features and depth discontinuities in reference 中國科學院 軟件 研究所 博士 學位 論文 基于 圖 象 的 快速 繪制 技術 的 研究 images , an efficient inverse wmping algorithm is pfoposed in chapter 3 for gcnerating nagcs of novel views by combining multiple eference images 帆 enhm different vie 呷 oints because continuous segnents determi 。 d by pairs ofedge pixels at co 。 spending epipolar lines are order kept , only pairs of edge pixels in the reference 渝 明 e e necess 叨 口 cowute to obtain generalized disparity of all points in the desired image as a result , sighficant acceleraion could be made in the endering pfo 比 鴕 two accelerating techiq 此 s e presented in this algori 山 mb accelerate the hole illing process his algorithm extends the reference images rom projection of single col : ii ’ ected surface in previously developed nvnverse w 出 下 er to ima 驢 s captured rom complex scene in chapter 4 , an 《 dent ibr method is prese 庇 仙 y takn ull 訕 antage of 呷 bies c 咖 the method can simulate the 3d details on sllri : ace of object successfully he 。 叩 proach , called rered ature mopmp consists of two pans at fst , an origi 。 ltexture with orthogonal displacements per pixel is deco 啊 osed into a series of new t6 刀 mfcs with each 他 lug a given displacement per pixel , called ae , ea atures , or lt hen hese lt e used to render the novel view by conventional texture mapping d avoid gaps n the endered hlla 驢 , some phels are to be interpolated nd extended in the 廠 kaccoding to the depth differe eee between two neighbor pixels in the original texture as these ltlt fc … e much storage nd therefore much time is equired to install ltlt into the text ’ ufc buffec an 舊 thod is pfoposed to co 呷 fcss the ltlt , nd the cottcspondingfclldering method is given experimental esults show that the new method is efficient , especially n rendering those objects with a smaller depth rnge compared withtheir size , such as relief surfaces of building
與己有的三維變換方法相比較,該方法不但成功地填補了由於投影區域擴張而產生的第一類空洞,而且成功地填補了由於空間深度非連續物體相互遮擋而產生的第二類空洞,從而方便地實現了虛擬環境中的漫遊;基於物體表面深度的連續性,本文提出了一個位移預測方法? ?此方法可以從單幅參考圖象獲得逆映射過程中所需要的目標圖象的位移信息,從而大大提高了演算法的效率:與通常的正向映射演算法相比,此演算法克服了多幅參考圖象所帶來的計算量成倍增長等問題,而且誤差較小。 2 )基於極線幾何的快速逆映射演算法。利用參考圖象的邊界信息與隱含的遮擋關系,以及極線幾何的性質,本文第三章提出了一個基於極線幾何的快速3 『一中國科學院軟體研究所博士學位論文基於圖象的快速繪制技術的研究逆映射演算法,從多幅參考圖象精確合成當前視點目標圖象。Employing the oblique projection shifting method, we have solved some graphic problem in descriptive geometry. it is very simple and fruitful to deal with difficult problems in orthographic drawing
摘要介紹了投影變換中的斜投射法及其在解決工程圖學一些問題中的應用。用這種方法可解決工程圖學中用正投影方法不便解決的圖示、圖解問題,而且具有應用范圍廣、作圖簡便的優點。It is based on the principle : under a number of angles, the x - ray attenuation in a cross section of a human body is measured by detector resulting in a set of profiles. this set of profiles is called the radon transform of the object in mathematics. the problem now is to reconstruct a two - dimensional image via inverting its radon transform
它所基於的成像原理是:人體的某個剖面在若干個角度上被x射線束照射,照射后x射線的衰減量被檢測器記錄下來,形成投影集合,數學上將這個投影集合描述為該剖面的radon變換,通過反演radon變換就能夠重建剖面的二維圖像。Computerized tomography ( ct ) is a typical non - invasive examination techniques in medicine, which can depict anatomical structures without damaging the human body. lt is based on the principle : under a number of angles, the x - ray attenuation in a cross section of a human body is measured by detector resulting in a set of profiles. this set of profiles is called the radon transfoim of the object in mathematics. the problem now is to reconstruct a two - dimensional image via inverting its radon transform
它所基於的成像原理是:人體的某個剖面在若干個角度上被x射線束照射,照射后x射線的衰減量被檢測器記錄下來,形成投影集合,數學上將這個投影集合描述為該剖面的radon變換,通過反演radon變換就能夠重建剖面的二維圖像。Such operations include rotation, translation, scaling, reflecting, orthographic projection, and perspective projection are provided to control the location of geometric models
其中包括旋轉變換、平移變換、比例變換、反射變換、正交投影變換和透視投影變換。利用這幾種變換的組合建立取景體。In two - view case, a method is presented for calculation 2d projective transformation and construction the virtual elements by combination of spatial points and lines. so more 3d invariants of object ' s spatial structures can be extracted from real elements and virtual eleme nts. ( 3 ) the geometric characteristics of 2d symmetric objects " in perspective images are lucubrated
( 2 )擴展了2d射影變換矩陣的求解方法,將單純利用點集對應的計算模式擴展到利用直線集、點線組合等多種類型來建立兩個射影平面的對應關系;總結了平面上基於點、直線元素可求解的多種3d不變量;提出了雙視圖下由點、直線元素的多種對應關系求解2d射影變換來構造「虛元素」的方法,結合「實元素」和「虛元素」可以提取更多的空間3d不變量。The conformal microstrip antenna with some unique character has been applied in many fields, especialy on speedy objects. in this paper, an efficient fdtd algorithm is introduced to analyse the microstrip antenna. firstly, the fdtd formula in descartes coordinate system and in cylindrical coordinate system are obtained from the time _ dependent maxwell equations using the yee algorithm in a calculating region where the dielectric parameters are independent of time and space. the choice of the space discretization units and the time discretization interval are discussed which are decided by the accuracy and stability respectively. the shape and setup of the excitation source are discussed too. the excitation source is chosen to be gaussian pulse in shape. secondly, the mur ' s first - order and second - order boundary condition are deduced in cylindrical coordinate system. the methods of transforming radiation fields from near zone to far zone in the frequency domain and in the time domain are presented when fdtd is applied to analyse the characteristics of far zone. finally, three kinds of microstrip antennas are analysed. they are a slot antenna that lies on a plane ground of a microstrip, a slot antenna that lies on a cylindrical ground of a microstrip and a microstrip line _ fed aperture coupled stacked rectangular patch antenna in cylindrical coordinate system
本文從麥克斯韋旋度方程出發,建立了笛卡兒坐標下無源空間中均勻無耗媒質的fdtd基本方程和圓柱坐標下無源空間中均勻無耗媒質的fdtd基本方程,詳細討論了fdtd法計算中時間步長和空間步長的選取原則以及激勵源的類型和設置;推導了mur一階和二階邊界條件在圓柱坐標下的差分格式;給出了在用fdtd法計算天線的遠場輻射特性時必需採用的頻域和時域近場遠場變換技術;最後用fdtd法計算了平面微帶縫隙天線、柱面共形微帶縫隙天線和柱面共形微帶層疊天線的輸入阻抗和遠區輻射場,並分析了天線的一些參數的變化對天線輸入阻抗的影響,得出了一些有用的結論。For bilateral symmetry objects, the techniques on symmetry - point detection and symmetry - axis extraction are presented based on harmonic conjugation relationship. for rotated symmetry objects, the techniques on rotated units description and rotated symmetry center extraction are presented based on center invariants of objects. further more, by using 3d invariants and 2d projective transformation, an approach to recover shape from part symmetry objects is realized on some conditions
( 3 )深入分析了2d對稱性目標透視成像的幾何特點,將共點四線交比用於目標輪廓上的關鍵點的特性描述中;利用調和共軛關系,提出了一種針對左右對稱型目標的對稱點檢測和對稱軸提取的演算法;利用交比關系構造了目標的形心不變量,提出了一種針對旋轉對稱型目標的旋轉對稱單元判定、旋轉中心提取的演算法;進一步利用3d不變量和2d射影變換,實現了一定條件下的對稱性目標的形狀恢復技術。We use a scaling matrix which make the algorithm generate sequences of point in trust region and the interior of the feasible set. because of the boundedness of the trust region, trust region algorithm can use non - convex approximate models
構造合理的仿射變換矩陣,在投影空間構造信賴域子問題,產生迭代方向,使迭代點既保持在信賴域內,又是嚴格可行域的內點。The projective transform occurs in the 2 - d imaging process, therefore in order to recognize airplane object, we have to find projective - invariant shape descriptor of object
由於目標的成像過程屬于射影變換,因此為了正確識別目標,必須找到一種具有射影不變性的目標形狀的描述方法。We systemically discuss how to uniquely decide an infinite plane homography matrix by using the structure information in scene and how to evaluate a homography matrix which convert affine reconstruction to euclidean reconstruction by solving absolute conic images. we give three constraints of absolute conic images and use these constraints to evaluate absolute conic images and then to rec
系統地討論了如何利用場景中的結構信息,來唯一地確定無窮遠平面的單應矩陣,進而由射影重構恢復仿射重構,以及如何通過絕對二次曲線的像求解將仿射重構變換為歐氏重構的單應矩陣。The thesis discusses the design process based on axiomatic design. the designer goes through a process whereby he / she can zigzags between domains - functional, physical, completes the decomposition and judges the independence of function and the consistency of decomposition
本文以公理設計為理論依據,應用公理設計理論設計框架,通過功能域和結構域之間的映射變換,完成產品的功能結構分解以及功能獨立性和設計分解一致性的分析,得到產品的等級結構模型,和各個組成部分之間的相互影響關系。Furthermore, by using the database with increased quantity and details need to handle the datasets which do not fit in ram ( out - of - core datasets ). meanwhile, advances in shading and image quality in general have raised the bar for image quality we would like to achieve in terrain rendering a in this thesis, we propose an efficient hardware - friendly framework - chunked lod, for large - scale terrain real - time rendering. within this framework, the approach for integrating multi - resolution representations of terrain geometry and terrain texture data is presented
變換和光照( transform & lighting ) 、立方環境材質貼圖( cubicenvironmentmaps ) 、頂點混合( vertexblending ) 、紋理壓縮( texturecompression )和凹凸映射貼圖( bumpmapping ) 、雙重紋理( dualtexture )四像素256位渲染等均可以在gpu中完成,大大減輕了cpu的壓力,對實時圖形渲染產生了深遠的影響,這其中包括實時地形渲染。Further, analyse the characteristic of the seismic wavefield of fractural reservoir and the influence caused by fracture density, property of the filled material and the strike of fracture. fifthly, in term of research of zhangshulun et al., concisely discuss the arithmetic of the plane wave forward modeling and migration with phase shift method, in prestack common offset gathers and check the arithmetic by numerical simulation
第四,用基於彈性?聲學近似的反射系數計算公式和本文提出的付氏變換子波生成法得到縫洞模型的反射系數模型和子波模型並用vrselrf波場延拓運算元對其進行地震波場數值模擬;進一步分析了縫洞儲層的地震波場特徵及縫洞密度、充填物性質和裂縫走向對其波場特徵的影響。Regular projective transformation
正則射影變換Another important content in this chapter is that we linearly calibrate the nonlinear parameters of camera based on the rectification features of lens and the fact that projective transform converts a line into a line
本章中另外一個重要的內容是,基於透鏡畸變的特點並根據射影變換保持直線不變的約束條件,線性地確定非線性內參數。分享友人